There is a widespread need for sampling plates such as those which, when used in conjunction with a measurement device, enable a diabetes patient to know their blood sugar levels—i.e. the concentration of glucose in their blood.
Traditional sampling plates function by receiving a spotted blood sample and directing at least some of the blood to a testing zone. The testing zone typically takes the form of a recess or well containing a quantity of glucose oxidase which chemically reacts with the blood to an extent and at a rate determined by the glucose concentration in the blood. The testing zone is typically furnished with a pair of electrode terminals which are conveniently bridged by the reaction mixture of the blood and glucose oxidase so as to allow for electrochemical readings by a corresponding measurement device. The electrochemical readings then provide an indication of blood glucose levels.
A problem with such traditional sampling plates is that blood spreading in and to the testing zone is often slow and/or non-uniform. For instance, blood spreading is often biased in the direction of an initial blood flow courtesy of surface tension. Sometimes a blood sample will not spread throughout the testing zone, and consequently measurements may be inaccurate or unreliable. This is a particular problem for sampling plates having a larger loading port to assist the less dextrous, such as the elderly or infirm.
It is an object of the present invention to provide an improved sampling plate.